1.Field of the Invention
The present invention relates to a wood planing machine, more particularly to a wood planing machine with a height adjustment mechanism that is adapted to be operated manually, mechanically and externally of a machine body with ease.
2. Description of the Related Art
Referring to FIGS. 1 to 4, a wood planing machine 10 according to U.S. Pat. No. 6,135,177 is shown to include a machine body 11 with two opposite side walls 111, and a cutter unit (not shown) mounted between the side walls 111. A workpiece support bed 13 is movably disposed in the machine body 11 between the side walls 111 and below the cutter unit (not shown), and is movable relative to the latter. A holding seat 15 is suspended in the machine body 11 below the bed 13 and between the side walls 111. The holding seat 15 includes a tubular body 151 formed with an upright passage 152 therethrough, and a radial pinion-mounting hole 155 in communication with the passage 152. A coupling member 14 is secured to a bottom side of the bed 13, and has a fixed vertical rack 141 that extends between upper and lower ends thereof. The coupling member 14 extends slidably through the passage 152 in the holding seat 15. A drive shaft 16 has a first coupling end 162 mounted rotatably on the tubular body 151 and extending across the pinion-mounting hole 155. A turning rod unit 17 is mounted on the machine body 11, and is coupled to a second coupling end 164 of the drive shaft 16 via a pair of gears 171,163. A pinion 161 is disposed in the pinion-mounting hole 155 of the holding seat 15, and is fixed on the first coupling end 162 of the drive shaft 16 for meshing with the vertical rack 141 in such a manner that rotation of the rod unit 17 results in vertical movement of the bed 13 toward and away from the cutter unit (not shown)
Manual turning of the rod unit 17 in order to move the support bed 13 in the machine body 11 is tiresome. The situation is aggravated in case the support bed 13 is relatively large and heavy.
Therefore, the object of this invention is to provide a wood planing machine with a turning rod unit which is operable manually and mechanically and which can overcome the aforementioned drawbacks that are associated with the use of the prior art wood planing machine.
Accordingly, a wood planing machine of the present invention includes a machine body, a workpiece support bed, and a height adjustment mechanism. The workpiece support bed is disposed movably in the machine body. The height adjustment mechanism includes a bed-turning rod unit, a slide element, a transmission device, and first and second bevel gears. The rod unit is mounted on the machine body and is operably associated with the support bed in such a manner that rotation of the rod unit results in movement of the support bed within the machine body. The slide element is disposed slidably on the rod unit, has a pair of spaced apart gear-holding arms. The slide element is slidable along the rod unit between first and second positions. The transmission device is mounted on the machine body, and has a toothed driving wheel exposed therefrom disposed adjacent to the slide element. The first and second bevel gears are mounted respectively on the gear-holding arms of the slide element such that the first and second gears are disposed on opposite sides of the driving wheel. The first and second bevel gears are coupled to the rod unit so as to be co-rotatable therewith. The slide element is movable to the first position, where the first bevel gear meshes with and is driven by the driving wheel to permit the rod unit to rotate in a first direction, and to the second position, where the second bevel gear meshes with and is driven by the driving wheel to permit the rod unit to rotate in a second direction opposite to the first direction.
Since movements of the workpiece support bed relative to the cutter unit can be done manually and mechanically, the aforesaid drawbacks encountered by the use of the prior art wood planing machine can be eliminated.